Also, Neill Blomkamp actually wanted him for the lead in Elysium, which would've allowed him to showcase his physical chops as an actor, and I think he could've pulled it off pretty well if he were cast.

Yeah, but I'm sure you know Blomkamp wanted to cast the Die Antwoord dude first, and those who had seen Chappie tend to agree that was a terrible idea, and kind of shows Blomkamp didn't know what he was doing... as if the rest of Elysium wasn't enough evidence for that already.